Djeffal, Khaled Boudjema, Abdelheq Mezouaghi, Salih Djilali, and Anwar Zeb. 2026. “Asymptotic Analysis of a Delayed SVIR Epidemic Model With Immigration”. Journal of Applied Nonlinear Dynamics 13 (3): 557-69. https://doi.org/10.5890/JAND.2024.09.011.